Saturday, January 15, 2005

Presentation, RDF Style

Xenon: An RDF Stylesheet Ontology "In this paper we...describe a more general mechanism for enabling heterogeneous composition for user agents. We term this mechanism a “stylesheet ontology” in analogy to the use of stylesheets on the Web and for XML as a way to abstract presentation from content. If we assume that stylesheets were deemed useful in the HTML and XML contexts, we claim that RDF possesses an even stronger need for stylesheets. HTML (and to some degree XML as well, when the schema in play is simple) is designed to yield human-readable content in a browser, whereas datasets that utilize the expressive power of RDF are rarely human-readable regardless of the syntax used."

"The Xenon stylesheet language is specified as an RDF ontology. In other words, the role the abstract syntax tree (AST) usually plays in functional languages such as XSLT or Lisp is played by an RDF fragment...By representing an AST in RDF, we have therefore drawn a correspondence between the terms “language” and “ontology”: a Xenon stylesheet is RDF written with respect to the Xenon ontology."

"The Xenon ontology provides a generic framework for describing how a resource may be transformed into a presentation as well as a template matching system for supporting heterogeneous composition."

"Because templates use RDF Schema to describe their parameters, both “code” and “data” have the same form and differ only by the complexity of the domain they are describing."

Update: Some browsers have a trouble with the above link. If you use "Save As" and open it with a PDF reader then it seems to work fine, rather than relying on the browser plugin.